Help diagnose A/C issue

Kyleag89

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Hey guys the warmer weather is coming and Id like to fix my AC. The compressor cycles on/off so I hooked my gauges up and tried to add some 134a. I added about 10oz of 134a and the system won't take anymore. The compressor is still cycling on/off and will now sometimes run for a little while but the low side is only 21-22psi and high side is around 150psi at 70s degrees ambient temp when running. What could cause the system to not take anymore refrigerant in despite it still being low?
 

07 Boss

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Why was the compressor cycling on and off? You need to figure that out. I mean it can be low pressure or high pressure or clutch or a few other things.

What is your static ac pressure at? Your running pressures do seem a little low but within acceptable limits seeing as it was not that hot out.
 

Kyleag89

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Without the compressor running and after sitting for awhile I measured 70psi on the high and low side. It seems to be acting like it's low on refridgerant but won't take any more in the system. I've tried multiple times and verified that refridgerant is flowing out of my can and gauges. The temperature just dropped here in MD again so I'll have to wait until this weekend when it gets hot again to diagnose more.
 
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Just for kicks, I asked the same question you did and got this. I had a similar issue years ago on another Ford, and the orifice was clogged, and the A/C shop fixed it. Hope you get the troubleshooting worked out.

Screenshot 2026-04-07 8.44.01 AM.png
 

Kyleag89

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Just for kicks, I asked the same question you did and got this. I had a similar issue years ago on another Ford, and the orifice was clogged, and the A/C shop fixed it. Hope you get the troubleshooting worked out.

View attachment 115078
Thank you very much, that sounds exactly like what is going on with my 07 and suspected. I noticed today that I can hear a hissing sound from the area where the orifice tube is located while the system is operating. I'm guessing it's restricted although it's still working now it won't be long again until it stops. Is there any chance my compressor might still be ok and the orifice tube is blocked by something else? There does seem to be an excess of leak sealing dye in the system from previous owners. I guess my next course of action is to order some spring clamp removal tools, have the system evacuated, then disassemble and inspect the components.
 
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